Lock nut



June 25, 19116;A ER A 2,402,583

\ y AIS', '//f I It? l5 7 Patented June 25, 1946 UNITED STATES PATENT OFFICE LOCK NUH'I` Frank J. Schumacher, Wilmette, nl.

` Application June 5, 1944, Serial No. 538,827`

(Cl. ISI- 19) 9 Claims. 1

This invention pertains to lock nuts for use on bolts and the like, and has as its general object the provision of such an article which can be made economically, which can be applied with facility to bolts of standard or conventional form, whichwill be highly effective to retain its connection and position on the bolt, which may be detached with facility when desired and reapplied and removed repeatedly, and which involves no mutilation', distortion or injury to the bolt to which it is applied or to the nut itself incident to attachment or detachment.

Other objects and advantages of the invention will be pointed out or indicated hereinafter or will be apparent to one skilled in the art upon an understanding of the present disclosure or upon actual use of embodiments of the invention. `To aid in explanation of the invention, I show in the accompanying drawing forming a part of this specification, and hereinafter describe, certain forms representing embodiments of it. It is to be understood, however, that these are pre sented for purpose of illustration merely, and hence are not to be construed in any fashion for the purpose of limiting the appended claims short ofthe true and most comprehensive scope of the parts in normal position preliminary to attachf Y ment of it to a bolt;

Fig. 2 is a top view of the nut illustrated in Fig. l, with a portion broken away;

Fig. 3 is a side elevation of the same embodiment;

Fig. 4 is a sectional elevation of a modified form; and

Fig. 5 is a diagram serving to illustrate, on an enlarged scale, certain features and particulars inthe action or operation of the device.

The nature of the invention will f be most quickly ascertained from a detailed description of these illustrative embodiments, which is as follows.

The lock nut illustrated in Figs, 1,2 and 3 comprises a leading or holding member I0, a fo1- lowing or clamping member I I, and a positioning member I2. The positioning member I2, although of value and utility, is not essential to the operativeness and full utility vof the lock nut, and may be omitted if desired. The leading and following members are shown 'as ofl conventional hexagonal contour, but it is obvious that they may be of other forms, and while it isof advan l the member II.

e 2 tage in certain particulars to have them of the same cross-sectional size and form, such is not essential.

The leading or holding member I0 is formed with a body portion I4 and a concentric neck or collar portion I5 of considerably less width than the body portion I4. The neck or collar portion I5 is formed with an upwardly tapering periph eral wedging surface I6 which terminates at an outwardly jutting shoulder or flange portion II which, in turn, has an upwardly tapering peripheral surface. The leading member I0 is tapped and threaded centrally, completely through the body and neck portions, with a screw thread ci uniform pitch and diameter. The neck portion is severed by a plurality of radial slots I8 and thereby subdivided into a plurality of segments or flanges I5a. Eachof these flanges bears on its inner surface a portion of the thread of the member I4, and said flanges are inherently resilient, the width of the slots I8 being sufficient to permit them an appreciable extent of inward deflection from their normal positions,

The following or clamping member II has a body portion I9 which is centrally tapped and threaded on the same pitch and radius as the leading member I0 and it is counterboredto provide a circular recess 2li concentric with and of ygreater diameter than its threaded bore. Thus the member II is formed with a clamping flange 2I which presents toward its center an inwardly tapering or converging circular wedging surface 22. This Wedging surface is shaped to conform to the taper and size of the exterior wedging surface I6 of the neck portion I5 but the axial length of the wedging surface 22 is only a minor fraction of the axial length of wedging surface I. outwardly beyond the wedgin-g surface 22, the flange ZI flares outwardly more rapidly as a circular constricting surface 24.

The leading and following members being formed as above described, they are assembled and connected to each other by placing them in concentric relationship with the flange I' of the member I0 within the constricting taper 24 of the member II, and then pressing them together with force sufficient .to spring the segments I5a inward far enough to permit the flange il of the leading member to pass through the circular orifice defined by the converging surface 22 oi' When the flange il has passed through that orifice, the segments lila spring back to their normal position by their inherent resilience, thus positioning flange I'I in overlapping relatlonship to the flange 2l within the recess 20 and with the wedging surface 22 in bearing contact with the upper fraction of the peripheral Wedging surface I6.

The wedging surfaces 22 and I6 should be smooth, circular in cross section, and of such circumferential size that they fit closely when the upwardly presented surface of the flange 2I is in abutment with the overhanging lower surface of the flange il;V Moreoven/the inclinationzor angle of the wedging surfaces I6 and 22 relative to the common axis of the threaded bores of the members I and II is well within the limiting angle of the coacting parts. y

In order to render immediately and clearly perceptible the rotational relationship of thee members I0 and Il whereat their threads are in phase, they may be provided onV their external surfaces with suitable indices 25, and in order to retain the members against being jostled out of phase relationship, as when the nuts are loose in packages or bins, the retentive action of the enacting surfaces I6 and 22 may be supplemented by use of a positioning member I2. This preferably is in the nature of a resilient annular member interposed between vfacing surfacesy of the members lll and II before they vare joined, and cf thickness such as to be placed under resilient tension by being compressed between them When they are pressed to their connected position. When so positioned, therresiliernt reaction of the member l2 serves to resist frictionally the relative rotation of the members I0 and I I and hence when they have been placed in phase relationship, serves to resist their displacement by forces incidental to `handling and the like. In the embodiments illustrated, the member I2 may be a ring of elastic rubber composition which, in its compressed association with the members IU and Il, serves to close the joint between them.

In the application of the nut to a bolt or the like, the members lli and II being in their phase relationship and the flange 2l in abutment with the flange Il, the nut is turned onto the bolty in conventional fashion and to the desired extent,.

which may be to the extent of setting up the member lli against an abutting surface. Having been turned onto the bolt to the desired extent, the wrench is then withdrawn from engagement with the member Ill Ibut kept in engagement with memberi I, and said member is screwed onto the bolt somewhat farther, What takes place is illustrated diagrammatically in Fig. 5, in which B designates the bolt and M designates an abutting member, such Aas a washer or element against which the body portion I4 of the leading or holding member Ill is set up. Inasmuch as bolts and nuts are made to certain standard specifications whichv provide for certain tolerances, or allowances in pitch diameter of threads and other dimensions of nuts and bolts designed for use together, and inasmuch as the tolerances from basic pitch diameter are` necessarily plus for nut threads .and minus for bolt threads, there almost invariably results, as between any nut and any bolt taken from normal production lots, a certain amount-of radial play, at least as regards individual turns of the threads. This play may not be ordinarily perceptible to the touch or to obser- 4 face of the bolt thread, as indicated at c. Likewise, there will 'be clearance between the top of the respective threads and the bottom of the opposed thread, as indicated at d. Because of illustrated by the thread portion yat the upper end vation, Ibut is ascertainalble or detectable by use of Fig. 5. inasmuch as this contact is first established at the upper ends of the flanges I5a, the farther setting up of the clamping member II serves to set up in the portions of the flanges ISU. which are within the recess 20 a. condition of tension which causes them to exert a continuous resilient pressure inwardly against the bolt by virtue of their own resiliency.

Consequently, in the event of subsequent change of the relative diameters of the nut and bolt, such as lmight occur, for example, from thermal expansion of the nut or reduction of the bolts diameter by longitudinal stretchingof it, the frictional gripping action of the flanges IEa upon the bolt is still maintained, because of their tensioned condition, Moreover, in event of shrinkage of the nut or swelling of the bolt, portions of-the flanges I5a withintherecess 20 are capable of elastic ilexion outwardly lto, accommodate the cha-nge in relationship. Consequently, it will be seen, the construction 'affords a lock nut having characteristics which enable it to remain firmly fixed and clamped in position on the bolt Yunder conditions which tend to change the relative diameters of the two.' It may be readily removed, when desired, simply-by backing oil the clamping member II until its flange 2l cornes into abutment with the flange I1 of the holding member A`Ill, and then unscrewing the latter with the member I I.w Y

The modified construction illustrated injig, 4 contains the characterizing featuresof, the construction described above, the same reference characters being applied to corresponding parts. It differs from the other embodiment in theform of the upper portions of the threaded flanges of the holding member, and the form of the recess of the clamping member. Flanges of theholding `member are here designated by the reference character I5. They have the converging peripheral wedging surfaces I6, as above described, but their upper portions are formed with peripheral wedging surfaces ISa which diverge from the `terminations of the converging surfaces I6. The clamping member I9 has the peripheral wedging surface 22 for wedging cooperation with the surfaces IS and it is also formed with a wedging surface 23 which flares from the terminus of the surface`22, and is adapted for bearing and wedging cooperation with the peripheral surface Ia ofthe lflanges. The two members are connectedgi-n the manner above described, viz., by pressing them-together sufllciently to spring the flanges VI5f.in Wardly enough to enter the recess 20. The wedging surfaces 22v and I6 cooperate Vas above described to clamp the holding member onthe bolt. The cooperation of the wedging surfaces 2,3 and I6aV hasasimilar effect in wedging the upper portions of the, flanges I5 inwardly against the bolt when thejmemberi II' isxbacked off on .the bolt relative to thermember I0' beyond the phase relationship illustrated in Fig. 4. Thus this construction is adapted to clamp the nut to the bolt when the holding and clamping members are relatively displaced in either longitudinal direction from their normal phase relationship.

With an understanding of the device and its operation, it will be appreciated that, in addition to the various advantages mentioned above, it has additional advantages from the manufacturing standpoint in that it is not necessary to hold it so closely to standard tolerance limitations.

What I claim is:

1. A lock nut comprising a leading member having a body portion with an integral coaxially extending collar portion which has a peripheral wedging surface tapering from the body portion, said body and collar portions being axially tapped to provide a threaded bore for screw threaded engagement with the threaded surface of a bolt and the collar portion being slotted lengthwise to provide a plurality of resilient segmental flanges bounding the bore, and a separate following member having a body portion which is axially tapped to provide a threaded bore for screw threaded engagement with the threaded surface of the bolt and is recessed concentrically therewith to form an inwardly jutting annular flange having an inwardly presented wedging surface spaced axially a substantial distance from the tapped portion, the axial length of the wedging surface being only a fraction of that of the peripheral wedging surface of the collar portion; said leading and following members being rotatably connected in coaxial relationship and with the annular wedging surface of the latter cooperating with the peripheral wedging surface of the former a substantial distance from the free end thereof, so that the two members may be turned onto a bolt coincidentally and the following member subsequently set up farther to swing the segmental flangeg inwardly into clamping engagement with the bolt.

2. A lock nut as specified in claim 1 and wherein the peripheral wedging surface is circular and the inwardly presented wedging surface is tapered to fit it.

3. A lock nut as specified in claim 1 and wherein the collar member has an outwardly jutting shoulder at the narrower end of its peripheral wedging surface, said shoulder being disposed within the recess of the following member and in overlapping relationship to the inwardly presented fiange thereof.

4. A lock nut as specified in claim 1 and wherein the collar member is provided at its narrower end with a peripheral flange jutting outwardly from its peripheral wedging surface and the annular flange of the following member is provided with a constricting surface converging toward its wedging surface.

5. A lock nut as specified in claim 1 and wherein the collar member is provided with an outwardly jutting shoulder at its narrower end in overlapping relationship with the annular flange of the following member, and tapering peripheral wedging surface portions of the collar segments have frictional bearing upon the inwardly presented wedging surface of said flange when said flange is in abutment with said shoulder.

6. A lock nut as specified in claim 1 and including also an elastically compressible positioning member interposed between and having frictional bearing upon opposed surfaces of the leading and following members.

7. A lock nut as specified in claim 1 and wherein the collar portion has a second peripheral wedging surface flaring from the smaller end of its tapering wedging surface, and the annular ange cf the following member has an interior wedging surface flaring from the inner terminus of its circular wedging surface and adapted for wedging cooperation with said second wedging surface of the collar member.

8. A lock nut for use on a male threaded member, comprising a holding member having an apertured body portion tapped to screw onto the male member and having also resilient flanges extending axially from the body portion, and a clamping member adjustably connected with the holding member and operable to deflect the ends of the flanges inwardly toward the male member and tension intermediate portions of the flanges to spring inwardly toward it, said clamping member having wedging engagement with the flanges at locations spaced from their ends.

9. A lock nut for use on a male threaded member, comprising a holding member having an apertured body portion tapped to screw onto the male member and having also resilient flanges extending axially from the body portion, and a clamping member adjustably connected with the holding member and operable to deflect the ends of the flanges inwardly toward the male member and tension intermediate portions of the flanges to spring inwardly toward it, said clamping member and flanges having cooperating wedging surfaces, and those of the clamping member being of less axial extent than those of the flanges.

FRANK J. SCHUMACHER. 

